Method for controlling connect and disconnect forces of a connector

ABSTRACT

A connector includes a housing having a bore with a housing groove disposed on an inside surface of the bore with a groove establishing a release angle between a housing groove bottom and a bore inside surface. A retainer defines a spring cavity between a retainer and the release angle and a circular radial canted coil spring is disposed in the spring cavity. A pin having a tapered end and a body diameter sized for sliding engagement with the bore is provided which includes a circumferential groove in the pin body for receiving the coil spring upon insertion of the pin into the bore. A circumferential groove includes a load angle for rotating the coil spring in an orientation in which the major spring axis is parallel to the release angle upon initial withdrawal of the pin from the bore. The coil is further compressed along the spring minor axis and expands radially upon continued withdrawal of the pin from the bore.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional application of U.S. application Ser. No. 11/111,109, filed Apr. 21, 2005, which is a divisional application of U.S. application Ser. No. 10/300,358, filed Nov. 19, 2002, which is a regular application of Provisional No. 60/333,103, filed Nov. 21, 2001, the contents of all of which are expressly incorporated herein by reference for all purposes.

The present invention is generally related to connecting mechanisms and is more particularly related to a connector that requires low force to connect and high force to disconnect.

BACKGROUND

Connectors have beef used in a great variety of applications, see, for example, U.S. Pat. Nos. 4,678,210, 4,763,683, 5,411,348 and 5,545.842. Each of the connectors referenced are directed to specific applications.

For example, U.S. Pat. No. 4,678,210, provides for a loading and locking mechanism directed to engaging and interlocking lightweight, delicate and many times fragile cylindrical parts with one another and provides for locking means for preventing separation of a first and second cylindrical member.

U.S. Pat. No. 4,763,683 is directed to a breakaway coupling for a coaxial fuel supply hose and provides for inner-connecting valve bodies, which define a center fuel supply passage.

U.S. Pat. Nos. 5,411,348 and 5,545,842 are directed to mechanisms for connecting and locking parts for effecting electromagnetic shielding, electrical conductivity, heat dissipation and environmental sealing.

The present invention provides for a connector utilizing a radial canted coil spring positioned within a housing groove in a manner for controlling connect and disconnect forces with a groove pin.

SUMMARY

A connector in accordance with the present invention generally includes a housing having a bore with a groove disposed on an inside surface of the bore. The bore groove establishes a release angle between a housing groove bottom and the bore inside surface.

A retainer is provided for defining a spring cavity between the retainer and the release angle and a circular radial canted coil spring is disposed in the spring cavity. The coil spring includes a centerline, a major and a minor axis, as hereinafter described.

A pin is provided having a tapered end and a body diameter sized for sliding engagement with the bore inside surface. A circumferential groove is formed in the pin body for receiving the coil spring upon insertion of the pin into the bore.

The circumferential groove includes a load angle for rotating the coil spring in an orientation in which the spring major axis is parallel with the release angle upon initial withdrawal of the pin from the bore. Continued withdrawal compresses the coil spring along the spring minor axis and upon further withdrawal of the pin from the bore the spring expands radially.

More particularly, the load angle is disposed below a centerline of the coil spring, should the load angle be above the centerline of the coil spring, disconnect would not be possible. This distinguishes the present invention from the hereinabove referenced prior art patents.

More particularly, the housing groove may include a coil groove stop) disposed between the release angle and the bore inside surface for limiting axial movement of the coil spring upon withdrawal of the pin from the bore.

The release angle may be disposed at between about 5° and about 90° to the centerline connector and is preferably disposed at between about 25° and about 65° to the connector centerline.

With the use of the stop means, hereinabove noted, the preferable release angle is between about 25° and about 30° to a centerline of the connector.

Still more particularly, the coil spring may be initially disposed within the cavity with a major axis disposed within an included angle of between about 30° and about 45°. In that regard, the coil spring may be initially disposed in the cavity in a convex orientation or in a concave orientation.

In all of the embodiments of the present invention, the load angle may be disposed at an angle of between about 50° and about 90° with the connector centerline and preferably at about 40° to the connector centerline.

Preferably, the coil spring has an inside diameter smaller than the pin body diameter, so that a force is provided which urges the coil spring toward the inside diameter of the pin groove. This facilitates insertion of the pin into the spring. In addition, preferably, the load angle means is greater than the release angle by at least 10.

Further, control of the ratio of connect to disconnect forces is provided by a spring having a ratio of coil width to coil height of between about 1 to about 1.5, preferably, between about 1 to about 1.04.

BRIEF DESCRIPTION OF THE DRAWINGS

The advantages and features of the present invention will be better understood by the following description when considered in conjunction with the accompanying drawings in which:

FIG. 1 is a side view in partial cross section, of a connector in accordance with the present invention generally showing a housing with a bore and groove therein, a retainer for defining a spring cavity, a circular radial canted coil spring disposed in the cavity and a pin having a tapered end with a body diameter sized for sliding engagement with the bore inside surface:

FIGS. 2-3 are front and right hand side views respectively, of a radial canted coil spring for use in the present invention;

FIGS. 4-8 are similar to FIG. 1 showing stepwise insertion, or connect and withdrawal, or disconnect, of the pin from the housing utilizing a release angle of 23° and further showing stop means disposed between the release angle and a bore inside surface for limiting axial movement of the coil upon withdrawal of the pin from the bore, the circumferential pin groove including a load angle for rotating the coil spring to an orientation in which the spring major axis is parallel to the release angle upon initial withdrawal of the pin from the bore;

FIG. 9 is an alternative embodiment to the present invention in which the radial spring is initially disposed in the cavity in a concave orientation with an included angle of 30°

FIG. 10 is a view of another embodiment to the present invention in which the radial spring is initially disposed within the cavity in a convex orientation having an included angle of about 30°;

FIGS. 11-16 are similar to the embodiment shown in FIGS. 1 and 4-8 showing stepwise positions of the pin, spring and housing during connect and disconnect with a release angle of about 33°;

FIGS. 17-22 are similar to the embodiment shown in FIGS. 11-16 with the spring being initially disposed in the cavity in a concave orientation;

FIGS. 23-28 are similar to the embodiment shown in FIGS. 11-16 with the spring initially disposed in the cavity in a convex orientation;

FIGS. 29-34 are similar to FIGS. 1 and 3-8 showing connect and disconnect steps with a release angle of about 45°;

FIG. 35 is a view similar to FIG. 17 with a release angle at 45°;

FIG. 36 is a connector similar to that shown in FIG. 10 with a release angle of 45′;

FIGS. 37-38 shown an embodiment in which the release angle is 65°;

FIGS. 39-40 are similar to the embodiment shown in FIGS. 37-38 utilizing a radial spring in a concave orientation with an included angle at 45° and a release angle of 65°; and

FIGS. 41-45 shows stepwise connect and disconnect sequential movement of the pin in housing utilizing a radial spring in a convex orientation with an included angle of 45° and a release angle of 65°.

DETAILED DESCRIPTION

With reference to FIG. 1 there is shown a connector 10, which includes a housing 12 having a bore 14, having a groove 16 disposed on an inside surface 18. The groove 16 establishes a release angle, or surface, 22 between a housing groove bottom 24 and the bore inside surface 18.

A retainer 28 is provided, which defines a spring cavity 30 between the retainer 28 and the release angle surface 22.

A circular radial canted coil spring 32 is disposed in the spring cavity 30 and a pin 34 having a tapered end 36 includes a body 38 having a diameter sized for sliding engagement with the bore inside surface 18.

The pin 34 includes a circumferential pin groove 48 having a load angle, or surface, 46, which provides a means for rotating the spring 32 to an orientation in which a spring major axis 54, see FIGS. 2 and 3, is parallel with the release angle 22 upon initial withdrawal of the pin 34 from the bore 14, as will be hereinafter discussed in greater detail.

Further withdrawal of the pin 34 from the bore 14 compresses the coil spring 32 along a spring minor axis 56 (again, see FIGS. 2-3) and expands the spring 32 radially upon continued withdrawal of the pin 34 from the bore 14 as also discussed hereinafter.

With specific referenced to FIGS. 2 and 3, there is shown the circular radial canted coil spring 32 having a centerline 60 and a turn angle A. The turn angle A is the angle between the centerline 60 of the spring 32 and a centerline of the coils 62. Such springs 32 are described in U.S. Pat. Nos. 5,139,243, 5,108,076 and 4,893,795. These patents are to be incorporated herewith in their entirety by this specific reference thereto for describing the types of radial springs suitable for the present invention.

This spring 32 includes an inside diameter, D, which is smaller than the air groove 48 diameter in order that the spring 32 is forced toward a pin groove bottom, or inside diameter, 66.

As shown in FIGS. 1 and 4-8, the release angle 22 is disposed at about 23° to a centerline 70 of the connector 10. It should be appreciate that this release angle may be disposed at between about 5° and 90° with the centerline 70 of the connector 10 in order to control, connect and disconnect forces, as hereinafter described.

With reference again to FIG. 1, the load angle, L, may be disposed at an angle of between about 50 and about 90° to the connector centerline 70, with about 40° being shown in FIGS. 1-8. This load angle surface contributes to the control of connects/release force ratios, as will be hereinafter discussed in greater detail.

As shown in FIG. 9, a radial spring 72 may be initially disposed in the cavity 30 in a concave orientation with an included angle of between about 30° and about 45°, 30° being shown. In this arrangement, a major axis 76 is initially oriented in a direction toward a connect direction of the pin 34, as shown by the arrow 78.

With reference to FIG. 10, there is shown a spring 82 disposed in a convex orientation within the cavity 30 having an included angle of between about 30° and about 45°, 30° being shown. In this arrangement, a coil major axis 84 is oriented against all insertion direction of the pin 34, as indicated by the arrow 86. It should be appreciated that common reference numbers used throughout the specification and all of the drawings represent identical or substantially similar components.

FIGS. 11-16 are similar to FIGS. 1 and 4-8 with a release angle of about 33°. Similarly, FIGS. 17-22 include a release angle at 33° utilizing the concave spring 72 and FIGS. 23-28 represent sequential connect and disconnect steps utilizing a convex spring 82 with a release angle of about 33°.

FIGS. 29-34 are similar to FIGS. 1 and 4-8 with a release angle at 45°. FIG. 35 is similar to FIG. 29 utilizing a concave spring 72 and FIG. 36 utilizing the convex spring 82 sequential connect/disconnect steps are represented in FIGS. 30-34.

FIGS. 37 and 38 are similar to FIG. 1, with a release angle of 65° with a corresponding concave spring 72 and convex spring 82 being shown in FIGS. 39 and 40.

FIGS. 41-45 shows the convex spring 82 with sequential connect and disconnect steps with a release angle of 65°.

Variation of the load angle 46 to the release angle 22 affects the force required to disconnect. The larger the release angle 22, the higher the force to disconnect. The larger the load angle 46 the greater the force required to disconnect. The greater the release angle 22 the greater the coiled 62 reflection and the greater the force required to disconnect.

As hereinabove noted, the closer the radial centerline 70 of the spring 32 to a load point 90 at the intersection of the pin body 38 with the load angle surface 46 (see FIG. 1) the higher the disconnect force preparing in mind. However, if the load point 90 is above the centerline 70 disconnect is not possible.

As shown in FIG. 1, the radial spring 32 has a 0° turn angle that is a major axis 94 (see FIG. 1) is parallel with the connector centerline 70. The concave springs 72 have an included angle of between 1° and 89° included angle and the convex spring 82 has a turn angle of between about 10 and 89° included angle, with 30° being shown in the FIGS. 17-22 and 23-38 respectively.

Concave springs 72 have the advantage of reduced force during initial connection when the concave angle is the same as the entry angle B, see FIGS. 1 and 9 of the pin 34 because minimum force is require to turn the spring 72 during connection. If the angles of the springs 32, 82 and the entry angle B are different the tapered end 36 of the pin 34 must turn the spring 32, 82 so that the major axis 94, 84 is parallel to the entry angle B of the tapered end 36 of the pin 34. The higher the variation that exists between the entry angle B of the tapered end 32 of the pin 34 and the turn angle of the spring the higher the force will be required to connect.

As shown in FIGS. 1 and 4-8, the radial spring 32 has a major axis 94, which is parallel to the centerline 70, 60 of the spring 32, see FIGS. 2-3. This type of spring 32 is desirable when the pin 34 has no chamfer, or tapered end, not shown.

In this case, the pin 32 outside diameter at entry will be parallel to the major axis of coil since the inside diameter of the spring 32 is generally smaller than the pin body outside diameter 38. A tapered end, or chamfer, 36 is desirable for facilitating assembly. The tapered end 36 reduces the force required to connect, which is important since an objective of the present invention is to maximize the ratio of disconnect to connect force.

The concave spring 72 has the advantage that the tapered end 36 of the phi 34 at the entry angle can be made parallel to the concave angle. In this manner, the initial force required to connect is minimized by making the spring concave angle the same as the tapered end 36.

The convex spring 82 requires substantially greater force at entry because it will be necessary to turn this spring 82 to the position of the entry angle of the tapered end 36 of the pin 34. Thus, the convex spring 82 is desirable and applications for a high entry force is desirable.

When connection takes place, the spring 32, 72, 82 positions itself at the normal or initial position at the bottom 66 of the pin groove 48. The force required to disconnect the connector 10 varies depending upon the type of spring 32, 72, 82 utilized be it the radial 32, radio concave 72 or radio convex 82 with the concave spring 72 requiring more force to disconnect than the radial spring 32 and convex spring 82. The reason for this force difference is due to the fact that the spring 32, 72, 82 must position itself with the major axis 76, 84, 94 of the coil parallel to the release angle surface 22 in the housing 12, and that requires turning of the spring 32, 72, 82.

The concave spring 72 requires greater ° of turning of the coil in the convex spring 82 and the more turning the spring 72, 82, the more stresses are parted to the spring causing greater force at disconnect. For these reasons, the spring 32, 72, 82 that requires minimum amount of turning results in minimum disconnect force and maximum turning results and maximum disconnect force. The concave spring 72 offers greater variation between disconnect and connect ratio because it requires less force to connect and greater forces to disconnect. When this feature is desirable to concave spring 72 has significant advantage.

In general, there are four main factors that affect the selection of the spring for maximum connect or disconnect ratio. They are:

a. A connector whose entry angle is parallel to the entry angle of the spring.

b. A coil that when deflected radially during the connecting process has the minimum amount of frictional force. A concave spring will have less frictional force.

c. A spring that when it is in the connect position will assume a turn angle that will require maximum turning, thus creating greater stresses on the spring and upon deflecting the disconnect will create a higher force.

d. A spring when deflected at disconnect will develop a higher force by varying the release angle. The higher the release angle, the higher the amount of spring deflection and the higher the force developed at disconnect.

In addition to the type of spring used, the many factors that will affect the disconnect force.

a. The larger the release angle of the housing, the greater the force required to disconnect.

b. The larger the load angle, the greater the force required to disconnect.

c. The larger wire diameter of the spring coil, the greater the force developed and the higher the force required to disconnect.

d. The smaller the ratio of the coil width to the coil height, the rounder the cross section of the coil will be and the higher the force to disconnect. The typical desirable ratio to develop higher force would be 1 to 1.04.

e. The smaller the back angle of the coil, the higher the force required to disconnect.

f. The smaller the front angle of the coil, the higher the force required to disconnect.

g. The relationship between the centerline of the spring coil in a connect position to the diameter of the pin at the load point. The shorter the radial distance between the centerline of the coil and the load point, the greater the axial force developed at disconnect and the greater the force required to disconnect.

h. The higher the modulus of elasticity of the wire, the higher the force to disconnect. Therefore, the selection of the spring material becomes a very important factor in maximizing the ratio of disconnect to connect.

i. The relationship between the load angle and the release angle. The load angle must always be larger than the release angle. The smaller the difference between the two, the greater the force required to disconnect. For most applications, a variation between the two of 70 appears to work satisfactorily.

j. The force required to stretch the spring during connection. The higher the force, the lower the ratio of disconnect to connect.

k. For this type of application, a spring force that increases with deflection is highly desirable. This characteristic can be achieved in a canted coil spring by controlling the ratio of the coil height to wire diameter. The smaller the ratio, the higher the force as a function of spring deflection.

With the present invention the ratio of disconnect force to connect force may be as high as 30 to 1. FIGS. 1 and 4-8 illustrate sequential position of the pin 34 and housing 12 utilizing a release angle 22 of the 23°. FIGS. 11-16 illustrate the connect disconnect steps utilizing a release angle of 33° and FIGS. 29-34 show the connect/disconnect steps with a release angle at 45°. These figures show a comparison between the effect that the release angle 22 has on the axial play and deflection of the spring 32. As hereinabove noted, the smaller the release angle 22 the lower the force developed. The larger the release angle 22 the higher the deflection and the higher the force developed to disconnect.

It should be appreciate that the actual play of the pin 34 varies with the release angle 22. By way of specific example, at small angles, that is 23° and 33° the axial play is approximately the same at about 0.007 inches. As a release angle 22 increases to 45° the axial play decreases to 0.004 inches with the same dimensions. See FIGS. 29-36. The axial deflection is 0. All of the springs 22, 72, 82 (see FIGS. 37-45).

Although there has been hereinabove described a specific connector with radial spring in accordance with the present invention for the purpose of illustrating the manner in which the invention may be used to advantage, it should be appreciated that the invention is not limited thereto. That is, the present invention may suitably comprise, consist of, or consist essentially of the recited elements. Further, the invention illustratively disclosed herein suitably may be practiced in the absence of any element, which is not specifically disclose herein. Accordingly any and all modifications, variations or equivalent arrangements which may occur to those skilled in the art, should be considered to be within the scope of the present invention as defined in the appended claims. 

1. A method of connecting a pin to a housing of a connector with a connect force, which is less than a disconnect force to disconnect the pin from the housing said method comprising: providing the housing with a bore and a housing groove, said housing groove comprising a bottom surface and a release surface that forms an angle to the bottom surface, wherein said angle between said bottom surface and said release surface is between 5° and 89°; providing a coil spring for use with the housing, said coil spring comprising a major axis, a minor axis, and a passage in between two coil sections; providing the pin with a longitudinal axis, a tapered end, and a pin groove comprising a groove bottom surface and a load surface that forms an angle to the groove bottom surface, which is less than ninety degrees; wherein the connect force is controlled by selecting the major axis of the coil spring to have a concave orientation to the longitudinal axis of the pin when the pin is moved in a first direction relative to the housing to connect the pin to the housing; wherein the disconnect force is controlled by selecting the angle of the release surface to bottom surface and the angle of the load surface to groove bottom surface that cooperate to force the major axis of the coil spring to rotate from a first position relative to the longitudinal axis to a second position relative to the longitudinal axis upon removing the pin in a second direction relative to the housing, which is opposite the first direction, to disconnect the pin from the housing; and wherein the disconnect force is at least one time greater than the connect force.
 2. The method according to claim 1, wherein the step of controlling the disconnect force comprises selecting the angle between the bottom surface of the housing groove and the release surface to be between 25° and 65°.
 3. The method according to claim 1, wherein the step of controlling the disconnect force comprises selecting the angle between the groove bottom surface of the pin groove and the load surface to be larger than about 40°.
 4. The method according to claim 1, further comprising selecting a spring coil width to coil height ratio of 1.04 or below.
 5. The method according to claim 1, wherein the pin groove comprises a load point and wherein the load point is located below a centerline of the coil spring.
 6. The method according to claim 1, further comprising the step of selecting the angle of the release surface to bottom surface to be smaller than the angle of the load surface to groove bottom surface.
 7. The method according to claim 1, further comprising the step of selecting an angle of the tapered end of the pin relative to the longitudinal axis so that the angle is parallel to the major axis of the coil spring.
 8. The method according to claim 1, wherein the bottom surface of the housing groove is spaced from the coil spring when the pin is connected to the housing to permit radial expansion of the coil spring.
 9. The method according to claim 1, wherein the housing is held steady relative to the pin while the pin is moved in the second direction to separate from the housing.
 10. The method according to claim 1, in the spring second position, the ma or axis is parallel to the to the release surface.
 11. The method according to claim 1, wherein the angle of the bottom surface and the release surface is selected of an amount cause the coil spring to deflect upon disconnect.
 12. The method of claim 1, wherein the disconnect force is from about eleven times to about thirty times greater than the connect force.
 13. A method of connecting a pin to a housing of a connector with a connect force, which is less than a disconnect force to disconnect the pin from the housing, the method comprising: inserting a pin into a bore of a housing by moving the pin in a first direction so that a canted coil spring is positioned between a pin groove and a housing groove to connect the pin to the housing; wherein: the pin comprises a longitudinal axis, an insertion end comprising an acute tapered surface relative to the longitudinal axis, and a body having an outside diameter and the pin groove, said pin groove comprising a groove bottom surface being generally parallel to the longitudinal axis and a load surface that forms an angle to the groove bottom surface and wherein the angle is less than ninety degrees; the housing comprises a bore having the housing groove disposed on an inside surface of said bore, said housing groove comprising a groove bottom surface being generally parallel to the longitudinal axis of the pin and a release surface that forms an angle to the groove bottom surface and wherein the angle is less than ninety degrees; the canted coil spring comprises a major axis and a minor axis; removing the pin from the housing so that the canted coil spring is no longer positioned between the pin groove and the housing groove by moving the pin in a second direction and causing the major axis of the spring to rotate from a first angle relative to the longitudinal axis to a second angle relative to the longitudinal axis; and wherein the disconnect force to disconnect the pin from the housing is one or more times greater than the connect force to connect the pin to the housing.
 14. The method according to claim 13, wherein the step of controlling the disconnect force comprises selecting the angle between the bottom surface of the housing groove and the release surface to be between 25° and 65°.
 15. The method according to claim 13, wherein the step of controlling the disconnect force comprises selecting the angle between the groove bottom surface of the pin groove and the load surface to be larger than about 40°.
 16. The method according to claim 13, further comprising selecting a spring coil width to coil height ratio of 1.04 or below.
 17. The method according to claim 13, wherein the pin groove comprises a load point and wherein the load point is located below a centerline of the canted coil spring.
 18. The method according to claim 13, further comprising the step of selecting the angle of the release surface to bottom surface to be smaller than the angle of the load surface to groove bottom surface.
 19. The method according to claim 13, further comprising the step of selecting an angle of the tapered end of the pin relative to the longitudinal axis so that the angle is parallel to the major axis of the coil spring.
 20. The method according to claim 13, wherein the bottom surface of the housing groove is spaced from the coil spring when the pin is connected to the housing.
 21. The method according to claim 13, wherein the second angle is the same as the angle between the release surface and the groove bottom surface.
 22. The method according to claim 13, wherein the coil spring is a canted coil spring.
 23. The method according to claim 13, wherein the angle of the bottom surface and the release surface is selected of an amount cause the coil spring to deflect upon disconnect.
 24. The method of claim 13, wherein the disconnect force is from about five times to about thirty times greater than the connect force.
 25. A connector having a pin and a housing structured to have a connect force to connect the pin to the housing being less than a disconnect force to disconnect the pin from the housing, said connector comprising: a pin longitudinal axis, a pin insertion end comprising a tapered surface relative to the pin longitudinal axis, and a pin body having an outside diameter and a pin groove, said pin groove comprising a groove bottom surface being generally parallel to the pin longitudinal axis and a load surface that forms an angle to the groove bottom surface; a housing bore comprising a housing groove disposed on an inside surface of said housing bore, said housing groove comprising a groove bottom surface being generally parallel to the longitudinal axis of the pin and a release surface that forms an angle to the groove bottom surface; a canted coil spring comprising a major axis and a minor axis located in both the pin groove and the housing groove when the pin is connected to the housing; wherein said major axis of said canted coil spring forms a concave orientation relative to the pin longitudinal axis prior to connecting the pin to the housing to control, at least in part, the connect force; wherein the angle of the groove bottom surface and the load surface of the pin is larger than the angle of the groove bottom surface and the release surface of the housing groove to control, at least in part the disconnect force; and wherein the disconnect force to disconnect the pin from the housing is greater than the connect force to connect the pin to the housing.
 26. The connector of claim 25, wherein the angle of the groove bottom surface and the load surface of the pin is at least forty degrees to about eighty nine degrees.
 27. The connector of claim 25, wherein the angle of the groove bottom surface and the release surface of the housing groove is about five degrees to about eighty nine degrees.
 28. The connector of claim 25, wherein the groove bottom surface of the housing groove is spaced from the canted coil spring when the pin is connected to the housing to permit radial expansion of the coil spring.
 29. The connector of claim 25, further comprising a retainer forming part of the housing groove.
 30. The connector of claim 25, wherein the connector is structured so that the pin is connectable to the housing when moving in a first direction and disconnectable from the housing when moving in a second direction. 